University of Colorado

Massimo Ruzzene

Yuning Guo

Matheus Rosa

An acoustic device includes a three-dimensional phononic crystal having cubic symmetry. The phononic crystal includes a first region filled with a first material and a second region filled with a solid material that is different from the first material. The second region is the solid complement of the first region. A boundary between the first and second regions is shaped as a single gyroid surface that has constant mean curvature and is not pinched off. The volume of the second region is greater than or equal to that of the first region. The first material may be a gas, such as air, or a fluid. The phononic crystal supports topological surface states, has a band structure with at least one degenerate point protected by nonsymmorphic symmetry, and exhibits negative refraction where two of its external surfaces meet.

Growing community of inventors

Boulder, CO, United States of America

Massimo Ruzzene